I propose to continue our work in cancer epidemiology that has developed at the Kaiser Permanente Medical Care Program in the past 1 1/2 decades and has been supported for 4 years by an Outstanding Investigators Grant, as follows: 1. Continue surveillance for possible carcinogenic effects of medicinal drugs in a cohort of 143,574 Kaiser Foundation Health Plan members using additional data resources of the program to test hypotheses. Study newer drugs, as appropriate, using the new region-wide pharmacy data system that is currently being implemented. 2. Continue follow-up of a cohort of over 100,000 persons who received multiphasic health checkups plus research questionnaires on smoking and alcohol use, to study cancer-producing effects of various tobacco products, alcoholic beverages, marijuana and other factors. 3. Continue to conduct nested case-control studies of possible chemopreventive factors in the above multiphasic cohort using a large collection of frozen serum specimens. 4. Continue to conduct studies of the efficacy of screening tests in preventing mortality from cancer. 5. Employ the flexibility afforded by the Outstanding Investigator Grant to study promising new leads concerning cancer etiology and control in the extensive data resources of Kaiser Permanente.